Field of the Invention
The invention relates to an encoder, and more particularly to an encoder with oil gas prevention structure.
Description of the Related Art
Encoders are widely used in many applications that require precise shaft rotation—including industrial controls, robotics, and automation equipment. The information, such as angular position, rotational speed, and direction are provided to control the phase, speed, and position of the motor.
The encoder is disposed with the shaft or the sleeve of the motor, wherein the code disc is rotated synchronously with the motor. In order to keep the smooth rotation, the oil lubrication is necessarily applied to the bearing.
However, the oil gas resulted from the high temperature during the rotation is diffused to contaminate the grating of the code disc such that the sensing accuracy is decreased.